Add BeagleV-Fire and librobotcontrol

See merge request docs/docs.beagleboard.io!66

Updated contributing guide

See merge request docs/docs.beagleboard.io!65

```shell-session
$ source ./venv-build-env.sh
$ cd projects/librobotcontrol/docs
$ doxygen
$ cd ../../..
$ sphinx-build -M html . public
```

Previously added instruction prevented the play from booting, this change fixes that.